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प्रश्न
A student sitting at the back of the classroom cannot read clearly the letters written on the blackboard. What advice will a doctor give to her? Draw ray diagram for the correction of this defect.
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उत्तर
Since, the student sitting at the back of the classroom cannot read clearly the letters written on the blackboard, it means the student is suffering from Myopia. The doctor will suggest her, a concave lens of suitable power which will bring the image back on retina and therefore the defect will be corrected.
The ray diagram for the correction of this defect is as below :
Correction for Myopia
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संबंधित प्रश्न
The far point of a myopic person is 80 cm in front of the eye. What is the nature and power of the lens required to correct the problem?
Explain with the help of labelled ray diagram, the defect of vision called myopia and how it is corrected by a lens.
What is long-sightedness? State the two causes of long-sightedness (or hypermetropia). With the help of ray diagrams, show:
(i) the eye-defect long-sightedness.
(ii) correction of long-sightedness by using a lens.
What is Hypermetropia (far sightedness)?
Given below is a diagram depicting a defect of the human eye? Study the same and answer the question that follow:
Draw a labeled diagram to show how the above mentioned defect is rectified using the lens named above.
A person is unable to see objects distinctly placed within 50 cm from his eyes.
(a) Name the defect of vision the person is suffering from and list its two possible causes.
(b) Draw a ray diagram to show the defect in the above case.
(c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm.
(d) Draw a labeled diagram for the correction of the defect in the above case.
Give Reason:
Why do we see clearly in the central region of the retina?
Give Technical Term:
The type of lens used to correct myopia is
What type of lens is used to correct Hypermetropia?
Differentiate the eye defects: Myopia and Hypermetropia
Myopia and hypermetropia can be corrected by:
Assertion: Myopia is the defect of vision in which a person cannot see distant objects clearly.
Reason: This due to eye-ball being too short.
Which of the following statement is correct?
Which of the following statement is correct?
Draw ray diagram showing myopic eye.
Observe the figure whether it is correct or not and explain the phenomenon.
State reasons for Myopia. With the help of ray diagrams, show the:
- image formation by a myopic eye, and
- correction of myopia using an appropriate lens.
Observe the following diagram and answer questions following it:
- Identify the defect of vision shown.
- List its two causes.
- Name the type of lens used for the correction of this defect.
Match the following:
| Column - I | Column - II |
| 1. Retina | a. Path way of light |
| 2. Pupil | b. Far point comes closer |
| 3. Ciliary muscles | c. near point moves away |
| 4. Myopia | d. Screen of the eye |
| 5. Hypermetropia | e. Power of accommodation |
Have a look at the posture of this girl who is reading a book and answer the questions which follow:
 |
- Name the problem she is facing.
- What are the two conditions shown in sections A and B of the eye as applicable to her.
- What kind of reading glasses does she need?
 |
 |
| A | B |
